Changeable sprocket-gear.



G. H. DOWNS.

GHANGEABLE SPROGKET GEAR.

APPLIUATION FILED KOV.13, 1908.

969,148. Patented Aug.30, 1910.

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"UNITED OFFICE.

GEORGE H. DOWNS, OF PORTLAND, OREGON, ASSIGNOR OF ONE-'HALF TO WILLIAM E.

- GRACE, OF PORTLAND, OREGON.

CHANGEAIBLE SPROCKET-GEAR.

To all whom it may concern:

Be it known that I, GEORGE H. DOWNS, a citizen of the United States, and a resident of Portland, in the county of Multnomah and State of Oregon, have invented a new and useful Improvement in Changeable Sprocket-Gears, of which the following is a specification.

This invention relates to the transmission of power by sprocket-gears and chain, and has for its object to obtain a driving gear so constructed and mounted on its shaft or axle as to permit its removal for the purpose either of replacing a worn or broken gear, or for substituting therefor a gear of larger or smaller diameter, to increase the speed or the power transmitted. For example, supposing my invention be applied to a common type of locomotive, by substituting a driving gear of larger diameter, I am enabled to so change the relations of the driving and driven gears as to adapt my locomotive for hauling a heavy load at slower speed, or by changing to a gear of smaller diameter I am enabled to pull a lighter load at greater speed. To this end my driving gear is constructed and arranged as illustrated in the accompanying drawings, in which:

Figure l is a side-elevation of my gears with a portion of one side broken away. Fig. 2 shows in its left half an end-elevation, and in its right half a vertical section of my gear; this view also illustrates a particular form of key preferably used by me; and Fig. 3 shows the lower half or part of the gear-body and a corresponding plan section of the sides.

The letters designate the parts described.

My gear consists of a body made in two half-parts a, a, provided with peripheral sprocket-teeth of convenient arrangement. The body parts are provided with bosses b, b, on which to receive the side-pieces or flange rings 0, c, which are also each made of two pieces or halves divided on a line d, at right angles to the divisional line of the two halves a, a of the body. The bosses I), b of the body parts project exterior of the sides or flange rings 0, c and said projecting boss-portions are each provided with registering perforated ears 6, e, to receive bolts f, by which the two halves of the gear body are drawn together on the shaft or axle- 9. As will be observed from Fig. 3, the ears are made with knuckles e which Specification of Letters Patent.

Application filed November 13, 1508.

Patented Aug. 30, 1910. Serial No. 462,477.

serve as retaining means for the side-pieces or flange rings. The sides 0, c are secured in place by bolts and nuts h, inserted through registering perforations in the gearbody and the sides or flange rings. To secure the two parts of the gear body on its shaft, I prefer to use two keys 2', c", which are constructed and arranged in the manner illustrated in Figs. 1 and 2. The central part, j, of each key is cut away, so as to leave projecting portions 7c, 70 at both ends. The shaft 9 is provided with slots of the length of the keys, in the exact places where the gear is to be mounted. The eye of the two-part gear body is provided with recesses or slots m, m in which to receive the keys 2', c", and said recesses have enlargements a, a at their outer ends adapted to receive the projecting key portions 70, 76.

I11 assembling the parts, the keys are first put in place on the shaft or axle, and then the two halves of the gear-body are placed over the same.

By the arrangement described, asis now apparent, I am enabled to readily and conveniently remove the driving gear from its shaft or axle and replace the same by a gear of larger or smaller diameter to obtain greater speed or greater power, as desired. In making such change, the length of the sprocket-chain would of course have to be changed to correspond, but this is readily done by using one of the well-known types of adjustable sprocket-chains, e. 9., such as commercially known by the name Morse silent chain.

Supposing my invention to be applied to a locomotive, it is obvious that it would be convenient to provide larger and smaller sized driving gears to be carried in the cab of the locomotive, so that the latter could be changed at any point along the road from one type to another, and thus the same locomotive could be used either for passenger or freight service, as circumstances may requlre.

Insulation Z, arranged substantially as illustrated in Fig. 1, is inserted between the parts when the gear is to be used in connection with electric motors.

My gear was especially designed for cases where flanges were desired, so as to prevent the sprocket-chain from leaving the gear under any circumstances. The removable sides provide the flanges, and because of being made as separate pieces facilitate the manufacture of my gear, for otherwise the cutting of the teeth on the gear would be a most laborious and expensive operation.

I claim:

1. The combination with a shaft, of a two-part gear body clamped on the shaft, and sides made in two parts removably bolted to the gear-body.

2. The combination with a shaft, of a twopart gear body clamped on the shaft, sides made in two parts removably bolted to the gear-body, said shaft being made with a key slot and the eyeof the gear-body with a corresponding recess having enlargements at its outer ends and a key inserted in said key slot of the shaft, said key having protrusions at its ends projecting into said enlargements of the key recess of the gearbody.

3. The combination with a shaft, of a twopart gear body clamped on the shaft, and sides made in two parts removably bolted to the gear-body, the line of division of said side-parts being at right angles to that of the body.

4. The combination with a shaft, of a twopart gear body clamped on the shaft, sides made in two parts removably bolted to the gear-body, the line of division of said side parts being at right angles to that of the body, said shaft being made with a key slot and the eye of the gear-body with a corresponding recess having enlargements at its outer ends, and a key inserted in said key slot of the shaft, said key having protrusions at its ends projecting into said enlargements of the key recess ofthe gear-body.

5. The combination of a two-part gearbody, means for clamping the body parts on a shaft, sides for the gear-body, said sides made in two parts, and bolts connecting the gear parts, there being registering perforations for the bolts through the sides and the gear-body.

6. The combination of a two-part gearbody, means for clamping the body parts on a shaft, sides for the gear body, said sides made in two parts, the line of division of said side-parts being at right angles to that of the body, and bolts connecting the gear parts, inserted through perforations provided in the sides and the gear body.

7. The combination of a two-part gear body provided with laterally projecting bosses, means applied to the bosses for clamping the gear body on a shaft, sides for the gear body, said sides being made in two parts and there being registering perforations for bolts through the sides and the gear-body, and bolts connecting the parts.

8. The combination of a two-part gear body provided with laterally projecting bosses having registering ears to receive bolts, sides made in two parts adapted to encompass the projecting bosses of the gear body, the line of division of said side-parts being at right angles to that of the body, and bolts connecting the parts, inserted through perforations provided in the sides and the gear body.

9. The combination of a two-part gear body provided with laterally projecting bosses having registering ears to receive bolts, said ears being adapted to constitute retainers for the sides, sides made in two parts adapted to encompass the projecting bosses of the gear body, the line of division of said side-parts being at right angles to that of the body, and bolts connecting the parts, inserted through perforations provided in the sides and the gear body.

GEORGE H. DOWNS. Witnesses CECIL Lone, T. J. GEIsLEn. 

